The npm depencies are installed in the .npm directoy in the package. You can add the traceur runtime by adding this to package.js:
Package.on_use(function (api) {
api.add_files(".npm/plugin/compileTraceur/node_modules/traceur/bin/traceur-runtime.js");
});
I forked your repository and fixed this: https://github.com/Sanjo/meteor-traceur
I also created a demo app: https://github.com/Sanjo/meteor-traceur-demo